We take a look at what the semifinalists need to do to stay in the race. By Eric Ditzian “American Idol” top 13 Photo: FOX Word on the reality-show street is, Wednesday’s (March 9) “American Idol” theme will have the top 13 contestants singing the tunes of artists they worship, but that’s the farthest we’ll drive into spoiler territory. Producers made the decision to pretape the performance episode , and while the Web is rife with info about what went down during the show, we’ve chosen to avoid all that. What’s the fun in reading about a reality competition before actually seeing it? So diving into the upcoming episode with only past shows to inform us, let’s take a look at each singer: who we’re excited about, who we honestly don’t care for and who better step it up or risk getting the boot on Thursday night. Ashthon Jones The 25-year-old has a whole lotta potential, but as someone wiser than us once said, potential just means you ain’t done sh– yet. Jones displayed boatloads of confidence and stage presence last week, yet never set sail toward the front of the “Idol” pack. She’s got some R&B gifts, but something about her take on Monica’s “Love All Over Me” felt too self-consciously like she was reaching for a diva moment. Ashthon, you’re not quite there yet. There’s a reason the judges had to use a wild card to save you. Show us your fun, energetic side first. Win some voters over. Wait a few more weeks before going diva again. Casey Abrams This kid has two things going for him: a free-wheeling, blues- and soul-infused instrument and a likable, everydude demeanor. Whether he’s too quirky to win the whole shebang (see: Bowersox, Crystal) is an open question. But there’s no doubting he’s a fan favorite, and even if his new performance doesn’t even approach his eyebrow-raising take on Screamin’ Jay Hawkins’ “I Put a Spell on You,” Abrams will be safe. We think we can count on him bringing the blues on Wednesday. Let’s see if he can tone down the growls a bit. Haley Reinhart Hey, we didn’t feel her rendition of Alicia Keys’ “Fallin’,” but America clearly did, voting her through to the next round. If she delivers another performance with notes that ping-pong across the musical scale, she might be in trouble. Like Jones, we encourage Haley to dial back the diva-tude and realize she’s never going to out-belt someone like Keys. Song choice will be the key to her survival, or lack thereof. Jacob Lusk Last week, we argued that while Lusk is potentially on the brink of a breakout performance, he’s not quite there; there was something simply too old-fashioned about it. Though a Luther Vandross tune is already on his “Idol” r